1. Field of the Invention
The invention concerns a transportation system employing at least one car moving on a guide track, a railroad type track, for example; the invention is more particularly concerned with system for automatically closing and opening the door or doors of the car while the car is moving slowly in a station.
2. Description of the Prior Art
U.S. Pat. Nos. 4,413,568 and 4,512,259 describe a transportation system using cars designed to transport passengers over average distances in the order of a few hundred meters, each car being designed to accommodate a limited number of passengers, in the order of ten passengers, for example. In a system of this kind a cable is driven in a closed loop and continuously along the guide track and the car is or the cars are hooked onto it, outside a station, by appropriate gripping means in order to be driven from one point to another. The system comprises at least one embarkation and/or disembarkation station. Each car in a station is uncoupled from the cable and taken up by decelerator or accelerator belts which come into contact with braked wheels carried by the car. The cooperation of these braked wheels with a succession of such belts makes it possible to displace the cabin at predetermined speeds within the station and in particular along the disembarkation platform and the embarkation platform, where its speed is the lowest, to enable passengers to leave or enter the car while it is moving slowly.
A system of this kind functions in a satisfactory way but for it to be operable under semi-automatic conditions, and even without human supervision, certain provisions must be implemented to protect the safety of the passengers. To this end the car or each car is fitted with at least one door and it is necessary to provide means for operating the door in a predetermined sequence while the car is moving in a station and for locking the door in between stations.
The invention proposes to provide a solution to all these requirements. The basic idea behind the invention consists in exploiting the fact that the car continues to move slowly during the embarkation and disembarkation phases in order to operate the doors, at least in part by means of the movement of the car itself, and to condition the operating sequences of at least some of the door operating and locking mechanisms to such slow displacement.